Phosphatidylinositol hydrolysis by human plasma phospholipase D.
A phospholipase D activity able to hydrolyze phosphatidylinositol has previously been described in the cytosol of human neutrophils. The experiments reported here demonstrate that this phosphatidylinositol-hydrolyzing phospholipase D activity is also present in human plasma. This activity was assessed by free inositol release from phosphatidylinositol substrate, by phosphatidate formation and by phosphatidylethanol formation through its capacity of catalyzing a transphosphatidylation reaction. This plasma enzyme activity shows an optimum pH of 8.0 and is inhibited by EGTA.
Balsinde
J
J
Centro de Investigaciones Biológicas (CSIC), Madrid, Spain.
Mollinedo
F
F
D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007295:Inositol Phosphates / Q000302:isolation & purification; D007700:Kinetics; D010716:Phosphatidylinositols / Q000378:metabolism*; D010739:Phospholipase D / Q000097:blood*; D010740:Phospholipases / Q000097:blood*
D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D010740:Phospholipases; D010739:Phospholipase D